คำตอบ - Trigonometry

The period of trigonometric functions is 360 degrees.

$$\sin \left(360°\right)=\sin \left(360-360°\right)$$

Subtracting one integer from another.

$$\sin \left(360-360°\right)=\sin \left(0°\right)$$

Computing the sine of zero degrees.

$$\sin \left(0°\right)=0$$